Veritas observations of day-scale flaring of m 87 in 2010 april
View/ Open
Full Text
Date
2012-02-01Author
Aliu, E.
Arlen, T.
Aune, T.
Beilicke, M.
Benbow, W.
Bouvier, A.
Bradbury, S. M.
Buckley, J. H.
Bugaev, V.
Byrum, K.
Cannon, A.
Cesarini, A.
Ciupik, L.
Collins-Hughes, E.
Connolly, M. P.
Cui, W.
Dickherber, R.
Duke, C.
Errando, M.
Falcone, A.
Finley, J. P.
Finnegan, G.
Fortson, L.
Furniss, A.
Galante, N.
Gall, D.
Godambe, S.
Griffin, S.
Grube, J.
Guenette, R.
Gyuk, G.
Hanna, D.
Holder, J.
Huan, H.
Hughes, G.
Hui, C. M.
Humensky, T. B.
Imran, A.
Kaaret, P.
Karlsson, N.
Kertzman, M.
Kieda, D.
Krawczynski, H.
Krennrich, F.
Lang, M. J.
LeBohec, S.
Madhavan, A. S
Maier, G.
Majumdar, P.
McArthur, S.
McCann, A.
Moriarty, P.
Mukherjee, R.
Nuñez, P. D.
Ong, R. A.
Orr, M.
Otte, A. N.
Park, N.
Perkins, J. S.
Pichel, A.
Pohl, M.
Prokoph, H.
Quinn, J.
Ragan, K.
Reyes, L. C.
Reynolds, P. T.
Roache, E.
Rose, H. J.
Ruppel, J.
Saxon, D. B.
Schroedter, M.
Sembroski, G. H.
Şentürk, G. D.
Skole, C.
Staszak, D.
Tešić, G.
Theiling, M.
Thibadeau, S.
Tsurusaki, K.
Tyler, J.
Varlotta, A.
Vassiliev, V. V.
Vincent, S.
Vivier, M.
Wakely, S. P.
Ward, J. E.
Weekes, T. C.
Weinstein, A.
Weisgarber, T.
Williams, D. A.
Zitzer, B.
Metadata
Show full item recordUsage
This item's downloads: 0 (view details)
Cited 32 times in Scopus (view citations)
Recommended Citation
Aliu, E. Arlen, T.; Aune, T.; Beilicke, M.; Benbow, W.; Bouvier, A.; Bradbury, S. M.; Buckley, J. H.; Bugaev, V.; Byrum, K.; Cannon, A.; Cesarini, A.; Ciupik, L.; Collins-Hughes, E.; Connolly, M. P.; Cui, W.; Dickherber, R.; Duke, C.; Errando, M.; Falcone, A.; Finley, J. P.; Finnegan, G.; Fortson, L.; Furniss, A.; Galante, N.; Gall, D.; Godambe, S.; Griffin, S.; Grube, J.; Guenette, R.; Gyuk, G.; Hanna, D.; Holder, J.; Huan, H.; Hughes, G.; Hui, C. M.; Humensky, T. B.; Imran, A.; Kaaret, P.; Karlsson, N.; Kertzman, M.; Kieda, D.; Krawczynski, H.; Krennrich, F.; Lang, M. J.; LeBohec, S.; Madhavan, A. S; Maier, G.; Majumdar, P.; McArthur, S.; McCann, A.; Moriarty, P.; Mukherjee, R.; Nuñez, P. D.; Ong, R. A.; Orr, M.; Otte, A. N.; Park, N.; Perkins, J. S.; Pichel, A.; Pohl, M.; Prokoph, H.; Quinn, J.; Ragan, K.; Reyes, L. C.; Reynolds, P. T.; Roache, E.; Rose, H. J.; Ruppel, J.; Saxon, D. B.; Schroedter, M.; Sembroski, G. H.; Şentürk, G. D.; Skole, C.; Staszak, D.; Tešić, G.; Theiling, M.; Thibadeau, S.; Tsurusaki, K.; Tyler, J.; Varlotta, A.; Vassiliev, V. V.; Vincent, S.; Vivier, M.; Wakely, S. P.; Ward, J. E.; Weekes, T. C.; Weinstein, A.; Weisgarber, T.; Williams, D. A.; Zitzer, B. (2012). Veritas observations of day-scale flaring of m 87 in 2010 april. The Astrophysical Journal 746 (2),
Published Version
Abstract
VERITAS has been monitoring the very-high-energy (VHE; > 100 GeV) gamma-ray activity of the radio galaxy M87 since 2007. During 2008, flaring activity on a timescale of a few days was observed with a peak flux of (0.70 +/- 0.16) x 10(-11) cm(-2) s(-1) at energies above 350 GeV. In 2010 April, VERITAS detected a flare from M 87 with peak flux of (2.71 +/- 0.68) x 10(-11) cm(-2) s(-1) for E > 350 GeV. The source was observed for six consecutive nights during the flare, resulting in a total of 21 hr of good-quality data. The most rapid flux variation occurred on the trailing edge of the flare with an exponential flux decay time of 0.90(-0.15)(+0.22) days. The shortest detected exponential rise time is three times as long, at 2.87(+1.65)(-0.99) days. The quality of the data sample is such that spectral analysis can be performed for three periods: rising flux, peak flux, and falling flux. The spectra obtained are consistent with power-law forms. The spectral index at the peak of the flare is equal to 2.19 +/- 0.07. There is some indication that the spectrum is softer in the falling phase of the flare than the peak phase, with a confidence level corresponding to 3.6 standard deviations. We discuss the implications of these results for the acceleration and cooling rates of VHE electrons in M 87 and the constraints they provide on the physical size of the emitting region.